yo what media are you growing in. i'm guessing it's rockwool since you have a 4 hour feeding cycle. I would water my plants 2-3 times through the night if i were you.

you can feed fairly often. i leave my drip system going 24-7, and my plants are doing great. i keep my water oxygenated with an airstone in my res, so the extra water does not seem to be detrimental. kind of a drip/dwc almost.

anyhow peace and good luck and i hope zandor pops his head in soon for you